1. Field of the Invention
This invention relates to, and has as its principal object provision of, novel ureas bearing a thiocarbamoylthio or carbamoylthio substituent. Specifically, these are 1-hydrocarbyl-3-(thiocarbamoylthio) ureas and 1-hydrocarbyl-3-(carbamoylthio)ureas, a new class of compounds that finds use as rubber curing agents.
2. Prior Art
The novel ureas of this invention have not been described in the chemical literature. The closest art known is that of S. R. Richter in U.S. Pat. No. 3,276,855, which discloses compounds of the type shown by the formula: ##EQU1##
Japanese Pat. No. 12,246 shows the production of Nacylureaus of the type: ##EQU2## by reaction of acyl isocyanates with sulfenamides or diaminosulfides.
F. Kurzer [J. Chem. Soc., London, 549, 3360 (1953)] reports the synthesis of N-aryl-N'-arylsulfenyl ureas by the following reactions:
ArNHCONH.sub.2 + Ar'SCl .fwdarw. ArNHCONH-S-Ar'
ArNCO + Ar'SNH.sub.2 .fwdarw. ArNHCONH-S-Ar'.